3rz-fe camshaft replacement

Hello,



I recently bout a 96 Tacoma (3rz-fe, 5spd, 4wd) with 213K. I checked valve clearance and a few were out of spec. So I put new bucket shims in. Fired it up and there was an immediate horrible, terrible, very loud, no good knocking noise from the top end. I took the valve cover off and discovered that the shim under the rear cam lobe on the intake side of the number 4 cylinder had been spit out of the bucket lifter, along with a bit of the lifter itself (which fortunately was not hard to find). The cam lobe had a decent ding in it (photo below)


Ouch!

I guess the shim was somehow not seated right? Anyhow, I have a new cam and lifter on the way. The service manual I found shows the exhaust cam being removed before the intake, and then being installed exhaust first followed by intake. My question is this: is it possible to remove ONLY the intake cam? Or do I have to remove the exhaust to do this?

Any input or advice is greatly appreciated!

 

This post does little to inspire members sitting on the fence about adjusting the valves on a 3RZ.
Please keep us posted on the outcome of your problem.

 

Alright,

Got the new camshaft and put that in today. Waiting on a new gasket for the timing chain tensioner, then I'll bar the engine over a few times and see if the timing marks still line up, and then I'll pucker up and fire the thing up.



Took a good look at the lifter that I replaced, and indeed it looks as though the shim had been resting on the edge of the cup and the lobe probably kicked it out the rest of the way.

So I think the lessons learned here are:

1. Inspect all the shims visually after replacement. The feeler gauge will not tell you if the shim is seated properly.

2. Bar the motor over a time or two and make sure things stay in place.

3. Don't wrench on important stuff in the dark by the light of an iPhone.

I'll let you know how tomorrow goes.

 

I did the shims on mine when I got it last summer. I had to remove the cams to get some out. Curiously some were hard to ensure they were totally seated so I could see how this could happen. Glad to see you got it fixed. Shims ain’t all that bad to deal with if you like to tinker on the engine over the weekend. I can imagine the horror you felt when the problem came apparent. Ooh it gives me the heebyjeebies

 

Yes, the feeler gage should have rejected that valve for undersize clearance. In fact, an unseated shim would depress the valve even on the base circle(the heel).

 

Well tomorrow turned into Saturday. I got the gasket and slapped it back together. Went to fire it up after barring the engine over several times. It cranked and cranked and cranked but didn't fire off. So I took it apart and pulled the distributor. Set that correctly and the thing fired up and purred like a kitty, but leaked oil out of the timing chain tensioner like a power washer.

So I've gone inside to drink some chocolate milk and sigh heavily. I guess I didn't get the mating surfaces clean enough.

 

Chocolate milk always makes things better

 

So the plot thickens...

There was a small bit of the old gasket stuck to the block where the tensioner sits. This was responsible for the rather aggressive oil leak.

Spent a bit cleaning that up, put it all back together. Fired it up. Large amounts of thick white smoke poured out of the tailpipe. I have attached a video taken a few seconds after shutdown. The engine is NOT running when the video was taken. When the engine was running there was huge amounts of smoke being pumped out.

https://youtube.com/shorts/9IJk0KpakeQ?feature=share

The smoke smells and feels oily. Not coolant here. This truck has never done this before.

So I have two hypothesis here.

1. Context: The truck has an exhaust manifold that is cracked in several places (I know, bad). Some oil from the spray generated by the leak ended up in the manifold and is being spit out.

2. In the few seconds the thing ran after the shim was spit out the valve stem cracked or something in the ensuing violence and oil is now pouring into the cylinder. But there really isn't a blue hue to the smoke at all, pretty much pure white.

Any thoughts are much appreciated here.

 

Pure white gas. Dark/blue is oil. If it smells sweet it's coolant.

 

Is it actually missing or does it run fine. Never get to overly concerned about white smoke on start up or for a bit after, water vapor is white and until the exhaust system warms up along with the engine, it is extremely common as any fossil fuel, when combusted, produces quite a bit of water vapor as a side product.

 

Ya that may be. However it was a lot more smoke or vapor than I would expect from normal cold startups. I guess I will pull the plugs tomorrow and see what I can see. Perhaps the head gasket just decided to suddenly give out. What an expensive valve adjustment this has turned out to be.

 

Oh and to answer your question, it was running absolutely fine no misses or anything weird.

 

Head gasket wouldn't have gone due to that. Was it been colder then normal or damper?

 

Mine sat for months before I cranked it up last week. It spit white steam for a good few minutes before all the assumed atmospheric moisture got expelled from the motor/exhaust pipe. Cleared up after a few minutes. I wouldn’t worry about it.

 

Thanks for all the replies. Bad news. Pulled the plugs this morning and borescoped the cylinders. First off the no 3 plug was shiny and smelled sweet. There was a nice bit of water sitting on top of the no 3 piston as well. So that's great.

Looked through the service records. A toyota dealer had done the head gasket and replaced the radiator in august of 2016, roughly 15,000 miles ago. I suspect that it was overheated and the head warped, meaning the replacement head gasket never sealed right, and here I am.

 

Replace the motor... JDM import. It's so much easier than screwing around changing the head and all the peripheral problems that will arise.... I know. And am a mechanic. It took me 14 hrs and 1700 in parts to replace mine with an OEM head I had rebuild. Certainly don't buy some cheap head off Amazon or Ebay

 

Your over thinking it....you have the expertise....

Toyota 2.4/2.7 2RZ/3RZ 8 port intake Assembled Cylinder Head | King Cylinder Heads


And part out what you already spent......
....I'll buy your shims.......



Good lesson in this too.....buy couple extra shim tools,when you mess with these...
not just that regular set.....Schley one,,,,,but get an extra like the motor cycle ones....or even copy and fab your own........
before the campaign.....a moded T-handle one would be awesome.....

.......and some times when you get in trouble here.....extra set of hands may be mandatory...

......unless you want to take the hood off and stand on top on the engine.....to get enough leverage.....

 

And RD is right......plan on spending a small forture on replacing parts.....
........I would want to do it all right while I was there.......but again shit load of money.....

 

I found it easier to remove the cams the second time I messed with those dumbass shims..(before I installed the rebuilt head) did it on the coffee table while watching Curse of Oak Island

 

I'm not a fan of the balance shafts......just another bearing fail point......
......this would allow you to do the delete kit........think the kit is like $100 from LCE.......